Head positioning device for dental x-ray systems



, 1970 w. R. SHILLER ET AL 3,539,805

HEAD POSITIONING DEVICE FOR DENTAL X-RAY SYSTEMS 3 Sheets-Sheet 1 FiledMarch 21, 1969 HEAD POSITIONING DEVICE FOR DENTAL X-RAY SYSTEMS Nov. W,191@ W. R. SHILLER ET AL 3 Sheets-Sheet 2 Filed March 21, 1969INVENTORS.

NOV. 10, 1970 5 ET AL 3,539,

HEAD POSITIONING DEVICE FOR DENTAL X-RAY SYSTEMS Filed March 21, 1969SSheetsr-Sheet 3 United States Patent,

3,539,805 IEAD POSITIONING DEVICE FOR DENTAL X-RAY SYSTEMS William R.Shiller, RED. 5, Box 597, Gales Ferry, Conn. 06335, and Mieczyslaw F.Zyra, 1002 Hampden St., Holyoke, Mass. 01040 Filed Mar. 21, 1969, Ser.No. 809,360 Int. Cl. G01n 21/00 U.S. Cl. 250-50 6 Claims ABSTRACT OF THEDISCLOSURE A head orientation and positioning fixture havingearengaging, nose-abutting, teeth-spreading components to be used as anaccessory for a panoramic scan dental X- ray machine, to sustain thesubjects head stably in anterior-posterior, superior-inferior, andlateral positions during the substantial fraction of a minute requiredto complete a full mouth X-ray exposure and also locate the subjectshead in essentially the same position at a later time for another fullmouth X-ray exposure whereby time-spaced X-rays can be overlaid tofacilitate detection of changes.

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

BACKGROUND OF THE INVENTION Panoramic X-ray equipment operates toarcuately scan a dental patients oral structures with a narrow X-raybeam directed through the mouth region of the head toward a film carrieron the opposite side of the patients head. Though the X-ray equipmenttraverses an arcuate path around the patients head, the beam isdiscontinuous during a traverse so as not to irradiate the spine. Alsothe beam direction shifts relative to the film carrier during a traverseso that a full mouth oral structure image is obtained on a rectangularfilm supported in the carrier. A chin support provided with suchequipment limits the patients range of movement during the exposureperiod but does not positively lock the patients head against allmovement during the relatively lengthy scan period. Movement of thepatients head during the scan period distorts at least part of the X-rayimage.

Additionally, for longitudinal studies of oral health a reproduciblemethod of X-ray exposure of a patients oral structures is required sothat changes may be detected by comparing or overlaying time displacedX-rays. Panoramic X-ray equipments advanced the feasibility oflongitudinal studies in such large measure that though such equipmentslacked a contrivance for head positioning that could be operated toposition the patients head at widely spaced time intervals in preciselythe same orientation relative to the X-ray equipment, the equipment hasbeen used advantageously by organizations responsible for the dentalhealth of large numbers of individuals over a period of years. Also,there must be a gap between the upper and lower teeth during panoramicX-ray but there has been no standard spacing technique which has mademore difiicult the comparison of serial X-rays.

An object of this invention is to stably and reproducibly position andorient the head and gap the upper and lower teeth of an individual forpanoramic scan X-ray.

A further object is to provide a reproducible method of exposingpanoramic X-rays of the oral structures so that changes over a period oftime can be observed.

Another object is to provide a precise head positioning device thatpermits exact orientation of the head in all planes and permitsduplication of this position for serial 3,539,805 Patented Nov. 10, 1970X-ray exposures and that does not interfere with X-ray exposure.

A further object is to provide improved techniques for longitudinalstudies of oral health of selected groups.

Other objects, advantages and novel features of the invention willbecome apparent from the following detailed description of the inventionwhen considered in conjunction with the accompanying drawings wherein:

FIG. 1 is a view of a preferred embodiment of this invention in use on asubject, and showing a part of the associated X-ray equipment;

FIG. 2 is a side view of the disclosed embodiment of the invention;

FIG. 3 is a plan view of a bite plate shown in FIG. 2; and

FIG. 4 is plan view on an enlarged scale of portion 4-4 of FIG. 2.

The invention embodiment shown in the drawings is a head positioningdevice between an X-ray source and film holder that moves around thehead positioning fixture 10. The fixture 10 includes a horizontal basemember 12 formed with a forked end presenting furcations 14 and 16through which extends traversely a winged clamping screw 18. Between thefurcations there is clamped a vertical support 20 that carries parallelhorizontal pivot pins 22 and 24. A pair of essentially identical rockerarm type lever members 26, 28 are retained by the pivot pins. The rockerarms have short lever arms 30, 32 that depend along the earpiece supportand curved arms 34, 36 several times longer than the arms 30, 32 toframe the lower part of the head to be X-rayed. The support 20 includesa shoulder portion 21 through which extends a screw 37 terminating in aconical cam tip 38. The contiguous lowor corners 39, 40 of the shortlever arms 30, 32 are angled to facilitate entry of the camming tip 38.Flat springs 42, 44 fixed to the sides of support 20 urge the shortlever arms against the camming tip 38. Ear plugs 46 are carried by theends of the curved arms 34, 36 approximately in line and are adjustableaxially. The support 20 is slotted to register with the screw 18 forconstraining the support 20 in one vertical position relative to base 12but permitting adjustment normal to base 12 into and out of the forkedend of base 12.

A bite pillar 50 is mounted on the outer end of base 12. At the upperend, the bite pillar 50 is stepped to present a nose abutment bar 52.Below the abutment bar, the bite pillar is for-med with a series ofparallel slots 54 inclined upwardly toward the opposite end of the base12. An oval bite plate 56 is supported in a slot 54. The rocker arms 34,36, the column 50 nose abutment 52, and bite plate 56 are of resinousmaterial essential transparent to X-ray.

The fixture 10 is fixed to a stanchion 58 carried by a dental chair.Brackets, not shown, supporting the stanchion permit the fixture to beswung into a dented-indexed position after a subject is in the chair andout of that position when the subject is ready to leave the chair. Thevertical position of the fixture is not adjustable. The chair seat isadjustable vertically as is conventional.

When a subject is seated in the chair, the fixture is moved intooperating position. The chair is adjusted. Then with the subjects headin position between the rocker arms, the camming screw 37 is rotated todisplace the rocker arms against the urging of the flat springs 42 and44 to position the ear plugs snugly into the subjects ears. Then thesubject tilts his head forwardly to Where his nose just touches the nosebar. An oval bite plate 56 is seated in that slot most comfortable forthe subject to bite upon. The support 20 is adjusted if necessary. Afterthe subject is thus positioned, the X-ray is taken and the slot numberin which the bite plate is seated is recorded so that the bite plate maybe positioned in the same slot during a future X-ray. The position ofthe adjustable bite plate and the nose abutment and earpieces locate thehead of the subject repeatably in the same position for serial X-raysfor longitudinal studies of oral health.

An alternative construction, not shown, for the column is to support acalibrated column frictionally in an opening or notch in the base orclamp on the base and a lock screw to retain the column in selectedvertical position; the bite plate is afiixed to the column.

We claim:

1. A fixture for use in combination with a panoramic scan type of dentalX-ray equipment comprising a base member adapted to be secured to adental chair at a constant height,

ear engaging means carried by the base,

a column carried by the base,

nose abutting means on the column, and

a bite plate for separating upper and lower teeth carried by the column.

2. A fixture as defined in claim 1 wherein said ear engaging meansincludes ear plug elements adapted to be seated in both ears of asubject to be X-rayed.

3. A fixture as defined in claim 2 wherein said ear engaging meansincludes essentially identical rocker arm members pivotally supported bythe base and having arms of unequal length, and

said ear plugs being supported at the ends of the longer arms of therocker arm members and directed toward each other.

4. A fixture as defined in claim 3 further including spring meansengaging the rocker arm members for urging the ear plugs away from eachother, and

means carried by the base and engaging the shorter arms of the rockerarm members and adjustable to space the ear plugs a selected distanceapart against the urging of the spring means.

5. A fixture as defined in claim 4 further including means securing saidbase to a dental chair with said rocker arm members and said columnoriented vertically,

said column being formed with a series of spaced slots inclined upwardlytoward the rocker arm members for seating the bite plate.

6. A fixture for use in combination with a panoramic scan type of dentalX-ray equipment comprising means carrying a bite element and a noseabutment;

a pair of substantially identical arms pivotally supported intermediatetheir ends on said means about parallel axes and in the same plane;

ear plugs secured to a pair of corresponding ends of the arms;

spring means engaging the arms for urging the ear plug ends apart andfor urging the other ends toward each other; and

an element carried by said means for adjusting the spread of the earplugs in opposition to the urging of the spring means.

References Cited UNITED STATES PATENTS 9/1955 Delk 2505O 10/1964 Blair250-50

